KR20060098586A - Liquid crystal display device equipped test pad and manufacturing method the same - Google Patents

Abstract

The present invention relates to a liquid crystal panel having a test pad drawn out from each other and directly exposed to the outside so as to easily identify output pulse waveforms of data and / or gate lines. Specifically, the present invention includes a first substrate having first to fourth edges; Data lines and gate lines intersecting longitudinally and horizontally on one surface of the first substrate to define pixels; Data and gate pads connected to one end of each of the data line and the gate line and positioned at first and second edges of the first substrate, respectively; A first test pad connected to the other end of the data line and positioned at a third edge of the first substrate; A thin film transistor provided at an intersection point of the gate line and the data line; A pixel electrode mounted on the pixel and connected to the thin film transistor; A second substrate bonded to the first substrate and exposing the first, second and third edges; A black matrix and a color filter formed on one surface of the second substrate facing the first substrate; A transparent common electrode covering the black matrix and the color filter; Provided is a liquid crystal panel provided with a test pad including a liquid crystal layer interposed between the first and second substrates. As a result, the signal transmission quality of the data line can be easily and simply measured using the first test pad.

Description

Liquid crystal panel equipped with a test pad and a method of manufacturing the same {Liquid Crystal Display device equipped test pad and manufacturing method the same}

1 is a perspective view of a general liquid crystal panel.

2 is a perspective view of a liquid crystal panel according to the present invention;

Figure 3 is an exploded perspective view of a portion of the liquid crystal panel according to the present invention.

4 is a schematic plan view of a first substrate of a liquid crystal panel according to the present invention;

5 is a perspective view of a modification of the liquid crystal panel according to the present invention.

<Description of the symbols for the main parts of the drawings>

102: liquid crystal panel 110, 130: first and second substrate

112,114,116,118: first to fourth edges

122, 124: data and gate pad 126: test pad

142,144: TCP

146,148 data and gate drive circuit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal panel provided with a test pad and a method of manufacturing the same. More specifically, the present invention relates to an output pulse waveform of data and / or gate lines. The present invention relates to a liquid crystal panel having a test pad drawn out from each other and directly exposed to the outside, and a manufacturing method thereof.

In recent years, as the society enters the full-scale information age, the display field that visually expresses various electrical signal information has been rapidly developed, and various kinds of flat panel display devices have been developed. FPD) was introduced.

Specific examples of such a flat panel display device include a liquid crystal display device (LCD), a plasma display panel device (PDP), a field emission display device (FED), and an electroluminescent display device. (Electroluminescence Display device: ELD) and the like, they have excellent performance such as thinning, light weight, low power consumption, and are rapidly replacing the conventional cathode ray tube (CRT).

The liquid crystal display has a high contrast ratio and is suitable for moving picture display, and thus is used most actively in the field of notebooks, monitors, and TVs. It has an image realization principle using optical anisotropy and polarization property of liquid crystals. That is, as is well known, the liquid crystal has a thin and long molecular structure, and has an optical anisotropy having an orientation in an array and a polarization property in which the direction of molecular arrangement changes according to its size when placed in an electric field.

Accordingly, a liquid crystal display device includes a liquid crystal panel formed by bonding a pair of first and second substrates having transparent field generating electrodes formed to face each other with a liquid crystal layer interposed therebetween, and a backlight for supplying light thereto. It includes an assembly (back light assembly), by controlling the electric field between the two field generating electrodes of the liquid crystal panel to artificially adjust the alignment direction of the liquid crystal molecules to generate a difference in transmittance and pass the light generated from the backlight assembly to the liquid crystal panel In order to express the difference in the transmittance to the outside, various images are displayed.

Recently, the active matrix type, which arranges pixels, which are the basic units of image expression, on a liquid crystal panel in a matrix manner and independently controls them by using a thin film transistor (TFT), is a color. It is attracting attention for its reproducibility and fast image conversion, and its composition is briefly examined.

As described above, a general active matrix liquid crystal panel includes first and second substrates bonded to each other with a liquid crystal layer interposed therebetween, and a plurality of data lines and gate lines cross each other on one surface of the first substrate to form a matrix. Pixels are defined, and thin film transistors are provided at intersections thereof and are connected one-to-one with the transparent pixel electrodes mounted in each pixel. In addition, a black matrix of a grid shape that exposes only pixel electrodes while covering non-display elements such as thin film transistors including data lines and gate lines on one surface of the second substrate, and red filled as an example filled in each of these grids. ), Green, blue color filters and all of them are provided with transparent common electrodes.

1 is a perspective view of the liquid crystal panel 2, in which the first substrate 10 and the second substrate 30 having the above-described configuration are bonded to each other with the liquid crystal layer interposed therebetween.

At this time, since the first substrate 10 has a larger area than the second substrate 30, two adjacent edges of the first substrate 10 are exposed to the outside when they are bonded to each other, and each of the data pads 22 connected to the data lines is exposed to the outside. ) And a gate pad 24 connected to the gate line. The data pads 22 and the gate pads 24 are connected to the data driver circuit 44 and the gate driver circuit 48 via TCP 42 and 46, respectively, and the latter gate driver circuit 48 The on / off of the thin film transistor per frame is scanned and transmitted to each gate line, and the former data driver circuit 44 transmits the image signal for each frame to the data line.

Therefore, when the thin film transistor selected for each gate line is turned on by the on / off signal of the thin film transistor that is scanned and transferred to the gate line, the image signal of the data line is transferred to the corresponding pixel electrode, which is common with the generated pixel electrode. The direction of arrangement of the liquid crystal molecules is changed by the electric field between the electrodes, indicating a difference in transmittance.

On the other hand, in the liquid crystal panel 2 having the above-described configuration, the signal transmission quality of the gate line and the data line is a decisive part for determining the image quality, and the signal is caused by various factors such as disconnection or short circuit of each line and wiring resistance. If it is distorted, it is directly related to the deterioration of image quality.

Accordingly, after the manufacturing of the liquid crystal panel 2, a process of testing the signal transmission quality of the data line and the gate line is followed, and the test process is performed on the data pad 22 and the gate pad 24 of the liquid crystal panel 2. A test input pulse is applied and the waveforms of the output pulses are extracted from the last end of each line and compared with each other.

However, as shown in the drawings, the first substrate 10 of the general liquid crystal panel 2 only exposes two edges of the data pad 22 and the gate pad 24 to the outside, and the ends of the data line and the gate line are removed. Since it is covered by the second substrate 30, there is no contact point for measuring the output pulse waveform. Therefore, a so-called decap operation is performed to peel off the two edges of the second substrate 30 coincident with the first substrate 10 so that the data line and the gate line ends are exposed to the outside for the test process.

However, such a decap process is limited to any liquid crystal panel 2, and thus relies entirely on manual work, and even a skilled person requires very careful attention, and in the process, undesired data lines or gate lines are undesired. Often disconnection occurs.

In addition, since the decapsulated liquid crystal panel is not recycled and discarded, it requires too much time and attention in order to measure the signal transmission quality of each line, and has a wasteful disadvantage.

Accordingly, the present invention has been made in order to solve the above-mentioned problems, and provides a concrete method for simpler and more convenient detection and recycling of the liquid crystal panel to be inspected at the same time in measuring output waveforms of data lines and gate lines of the liquid crystal panel. The purpose is.

The present invention comprises a first substrate having first to fourth edges to achieve the above object; Data lines and gate lines intersecting longitudinally and horizontally on one surface of the first substrate to define pixels; Data and gate pads connected to one end of each of the data line and the gate line and positioned at first and second edges of the first substrate, respectively; A first test pad connected to the other end of the data line and positioned at a third edge of the first substrate; A thin film transistor provided at an intersection point of the gate line and the data line; A pixel electrode mounted on the pixel and connected to the thin film transistor; A second substrate bonded to the first substrate and exposing the first, second and third edges; A black matrix and a color filter formed on one surface of the second substrate facing the first substrate; A transparent common electrode covering the black matrix and the color filter; Provided is a liquid crystal panel including a liquid crystal layer interposed between the first and second substrates.

In this case, the first and third edges are opposed to each other, and the first test pad is formed of the same material in the same process as the data line, and the second substrate is characterized in that the fourth edge And expose a second test pad connected to the other end of the gate line and positioned at a fourth edge of the first substrate, wherein the second test pad is in the same process as the gate line. Characterized in that formed of the same material.

In addition, the present invention provides a liquid crystal panel manufacturing method according to the above description, a) comprising the first substrate and the gate pad, the gate line, the data pad and the data line, the first test pad, the thin film transistor and Forming the pixel electrode; b) forming the black matrix, the color filter, and the transparent common electrode on one surface of the second substrate; c) bonding the first and second substrates to each other with the liquid crystal layer interposed therebetween.

In this case, the method may further include cutting the third edge of the first substrate exposed after the step d), wherein the step a) includes a second test pad connected to the gate line of the first substrate. And forming at the fourth edge, wherein the second substrate of step d) exposes the fourth edge, and further comprising cutting the exposed fourth edge after step d). Characterized in that.

In addition, the present invention comprises a first substrate having a first to fourth edge; Data lines and gate lines intersecting longitudinally and horizontally on one surface of the first substrate to define pixels; A gate and a data pad connected to one end of each of the data line and the gate line and positioned at first and second edges of the first substrate; A first test pad connected to the other end of the gate line and positioned at a third edge of the first substrate; A thin film transistor provided at an intersection point of the gate line and the data line; A pixel electrode mounted on the pixel and connected to the thin film transistor; A second substrate bonded to the first substrate and exposing the first, second and third edges; A black matrix and a color filter formed on one surface of the second substrate facing the first substrate; A transparent common electrode covering the black matrix and the color filter; Provided is a liquid crystal panel including a liquid crystal layer interposed between the first and second substrates.

In this case, the first and third edges are opposed to each other, and the first test pad is formed of the same material in the same process as the gate line.

In addition, the present invention provides a method for manufacturing a liquid crystal panel according to the above description, a) comprising the first substrate and the gate pad, the gate line and the first test pad, the data pad and the data line, the thin film transistor and Forming a pixel electrode; b) forming the black matrix, the color filter, and the transparent common electrode on one surface of the second substrate; c) bonding the first and second substrates to each other with the liquid crystal layer interposed therebetween, and in this case, the third edge of the first substrate exposed after step d). It characterized in that it further comprises the step of cutting, with reference to the drawings will be described in more detail the present invention.

2 and 3 are exploded perspective views of a liquid crystal panel 102 according to the present invention and a part of the liquid crystal panel 102 according to the present invention, wherein the first substrate 110 and the second substrate are bonded to each other with the liquid crystal layer 200 therebetween. And a substrate 130.

More specifically, a plurality of data lines 152 and gate lines 154 vertically and horizontally intersect on one surface of the first substrate 110 called a double lower substrate or an array substrate to define the pixel P. The thin film transistor T is provided at the intersection of these two lines and is connected one-to-one with the transparent pixel electrode 156 provided in each pixel region P. FIG. In this case, the thin film transistor T includes a source electrode connected to the data line 152, a drain electrode connected to the pixel electrode 156, a gate electrode connected to the gate line 154, and a semiconductor layer serving as a conductive channel.

In addition, the second substrate 130 facing the same is called an upper substrate or a color filter substrate, and one surface thereof has a data line 152, a gate line 154, and a thin film transistor of the first substrate 110. A black matrix 162 having a lattice bordering the pixel region P so as to expose only the pixel electrode 156 while covering a non-display element such as T), and to correspond to each pixel region P inside the lattice. One example of sequentially repetitive arrangement includes R (rea), G (green), and B (blue) color filters 164a, 164b, and 164c, and a transparent common electrode 166 covering all of them.

Although not clearly shown in the drawings, the upper and lower alignment layers for determining the initial molecular alignment direction of the liquid crystal are interposed between the two substrates 110 and 130 and the liquid crystal layer 200, and the liquid crystal layer filled therebetween ( In order to prevent leakage of the 200, a seal pattern is formed along the edges of both substrates to be sealed, and selectively transmit only a specific polarized light to at least one outer surface of the first and second substrates 110 and 130. The polarizing plate to make is attached.

In particular, the first substrate 110 according to the present invention has a larger area than the second substrate 130 and at least three edges of the four edges of the first substrate 110 are exposed to the outside when they are bonded to each other. When the four edges of the first substrate 110 are arbitrarily referred to as the first to fourth edges 112, 114, 116, and 118, the liquid crystal panel 102 according to the present invention has three edges of the first substrate 110, that is, the first to first edges. Three edges 112, 114, and 116 are exposed out of the second substrate 130.

The data pad 122 is connected to one end of the data line 152, the gate pad 124 is connected to one end of the gate line 154, and the test pad 126 is connected to the other end of the data line 152.

That is, referring to FIG. 4 which shows a schematic plan view of the first substrate 110 of the liquid crystal panel 102 according to the present invention, the first and second edges 112 and 114 adjacent to each other of the first substrate 110 are referred to. ) Are provided with a data pad 122 and a gate pad 124, respectively, and are connected to the start points of the data line 152 and the gate line 154, and separately from the third edge 116 of the first substrate 110. Test pads 126 connected to the end points of the data lines 152 are provided, and the first to third edges 112, 114, and 116 remain exposed to the outside even after bonding with the second substrate 130. .

Therefore, while applying a predetermined test input pulse to the data line 152 through the data pad 122, it is easy to extract the output pulse waveform appearing at the final end of each data line 152 through the test pad 126. By comparing these with each other, the signal transmission quality of the data line 152 can be easily confirmed. In this process, since the test pad 126 is exposed to the outside, the test pad 126 may be used as a contact point for directly detecting an output pulse of the data line 152 without a separate decap process.

When the test process is completed, the data pad 122 and the gate pad 124 are connected to the data driver circuit 144 and the gate driver circuit 148 through the TCPs 142 and 146, respectively. The third edge 116 of the first substrate 110 provided with the test pad 126 may be cut to correspond to the corresponding second substrate 130 to have the same shape as a conventional liquid crystal panel.

That is, in the liquid crystal panel 102 according to the present invention, the third edge 116 of the first substrate 110 exposes the test pad 126 as a contact point for measuring signal transmission quality of the data line 152. Since it is intended to be cut in an appropriate process after the test step, furthermore, if necessary, the test pad 126 is withdrawn from some data lines 152 to be measured for signal transmission quality without being connected to all the data lines 152. It is also possible.

However, the test pad 126 is preferably made of the same material in the same process as the data line 152 so that the signal transmission characteristics of the data line 152 can be accurately measured. In order to prevent the increase, it is advantageous that the third edge 116 on which the test pad 126 is provided faces the first edge 112 on which the data pad 122 is provided.

On the other hand, the general manufacturing process of the liquid crystal panel 102 is a thin film deposition process, the photoresist (photo resist) is applied to the upper part of the completed thin film and then exposed and developed by using a mask engraved with a predetermined pattern Photolithography, which exposes a selected portion of the thin film, an etching process that removes the selected portion of the thin film, and a cleaning process that removes residual photoresist, may be repeated several times. Each of the components of the thin film transistor T, the pixel electrode 156, and the like is completed, as well as the data line 122 and the gate pad 124 drawn from the 152 and the gate line 154.

Therefore, the test pad 126 according to the present invention can also be completed integrally by partially modifying the mask pattern in the manufacturing process of the data line 152, and an indium tin of an insulating layer, a protective film, or a pixel electrode 156 is formed thereon. When an oxide (Indium Tin Oxide (ITO)) is deposited, it is preferable that only the test pad 126 of the same material as the data line 152 is exposed by removing it, so that accurate signal transmission quality can be measured.

In addition, in the above description, the test pad 126 is arbitrarily described as being connected to the data line 152. Instead, the test pad 126 exposes the fourth edge 118 of the first substrate 110 according to the purpose, and then gates the corresponding portion. It is also possible to provide a separate test pad connected to the end of the line 154, through which it is possible to test the signal transmission quality of the gate line 154.

In addition, as shown in the perspective view of Figure 5 showing a modified example of the liquid crystal panel 102 according to the present invention, the same reference numerals are given to the same parts having the same role as the previous description is omitted.

Variations according to the present invention can expose all of the first to fourth edges 112, 114, 116, 118 of the first substrate 110 to the outside of the second substrate 130, as seen from the double first and second edges 112, 114. A first test pad 126 and a fourth edge 118 connected to an end of the data line (see 152 of FIG. 4) at the data pad 122 and the gate pad 124. It is also possible to provide a second test pad 128 connected to an end of the gate line (see 154 of FIG. 4). In this case, the measurement of the signal transmission quality of the data line (see 152 of FIG. 4) by applying a predetermined input pulse to the data pad 122 and then detecting the output pulse from the first test pad 126 has been described above. After applying a predetermined input pulse to the gate pad 124, it is possible to measure the signal transmission quality of the gate line 154 by detecting the output pulse from the second test pad 128. The first and second test pads 126 and 128 may be provided to measure the signal transmission quality of both 152 and the gate line 154.

In this case, it is preferable that the first edge 112 of the first substrate 110 including the data pad 122 and the third edge 116 provided with the first test pad 126 face each other, and the gate The second edge 114 provided with the pad 124 and the fourth edge 118 provided with the second test pad 128 are preferably opposed to each other to reduce the length of each line so as to eliminate unnecessary line resistance. Can be.

In addition, after such a test process, the third edge 116 provided with the first test pad 126 and the fourth edge 128 provided with the second test pad 128 may be cut to have a general liquid crystal panel configuration. Of course.

As described above, the liquid crystal panel according to the present invention may omit a decap process for measuring the signal transmission quality of the data line and / or the gate line, and is simply and accurately by using a test pad drawn at the end of each line. This has the advantage of testing the signal transmission quality of each line.

In addition, the liquid crystal panel according to the present invention has an advantage that can be recycled by cutting and removing the test pad part after the test of each line is completed.

Claims (14)

A first substrate having first to fourth edges; Data lines and gate lines intersecting longitudinally and horizontally on one surface of the first substrate to define pixels; Data and gate pads connected to one end of each of the data line and the gate line and positioned at first and second edges of the first substrate, respectively; A first test pad connected to the other end of the data line and positioned at a third edge of the first substrate; A thin film transistor provided at an intersection point of the gate line and the data line; A pixel electrode mounted on the pixel and connected to the thin film transistor; A second substrate bonded to the first substrate and exposing the first, second and third edges; A black matrix and a color filter formed on one surface of the second substrate facing the first substrate; A transparent common electrode covering the black matrix and the color filter; Liquid crystal layer interposed between the first and second substrate Liquid crystal panel comprising a. The method of claim 1, And the first and third edges face each other. The method of claim 1, The first test pad is formed of the same material in the same process as the data line. The method according to any one of claims 1 to 3, wherein The second substrate exposes the fourth edge, A second test pad connected to the other end of the gate line and positioned at a fourth edge of the first substrate Liquid crystal panel further comprising. The method of claim 4, wherein The second test pad is formed of the same material in the same process as the gate line. A liquid crystal panel manufacturing method according to any one of claims 1 to 3, wherein a) forming the gate pad, the gate line, the data pad, the data line, the first test pad, the thin film transistor, and the pixel electrode with the first substrate; b) forming the black matrix, the color filter, and the transparent common electrode on one surface of the second substrate; c) bonding the first and second substrates together with the liquid crystal layer interposed therebetween; Method of manufacturing a liquid crystal panel comprising a. The method of claim 6, Cutting the third edge of the exposed first substrate after step d) Method of manufacturing a liquid crystal panel further comprising. The method of claim 6, The step a) includes forming a second test pad connected to the gate line at the fourth edge of the first substrate. Method of manufacturing a liquid crystal panel further comprising. The method of claim 8, The second substrate of step d) exposes the fourth edge, Cutting the exposed fourth edge after step d) Method of manufacturing a liquid crystal panel further comprising. A first substrate having first to fourth edges; Data lines and gate lines intersecting longitudinally and horizontally on one surface of the first substrate to define pixels; A gate and a data pad connected to one end of each of the data line and the gate line and positioned at first and second edges of the first substrate; A first test pad connected to the other end of the gate line and positioned at a third edge of the first substrate; A thin film transistor provided at an intersection point of the gate line and the data line; A pixel electrode mounted on the pixel and connected to the thin film transistor; A second substrate bonded to the first substrate and exposing the first, second and third edges; A black matrix and a color filter formed on one surface of the second substrate facing the first substrate; A transparent common electrode covering the black matrix and the color filter; Liquid crystal layer interposed between the first and second substrate Liquid crystal panel comprising a. The method of claim 10, And the first and third edges face each other. The method of claim 10, The first test pad is formed of the same material as the gate line in the same process. A liquid crystal panel manufacturing method according to any one of claims 10 to 12, wherein a) forming the gate pad, the gate line, the first test pad, the data pad, the data line, the thin film transistor, and the pixel electrode with the first substrate; b) forming the black matrix, the color filter, and the transparent common electrode on one surface of the second substrate; c) bonding the first and second substrates together with the liquid crystal layer interposed therebetween; Method of manufacturing a liquid crystal panel comprising a. The method of claim 13, Cutting the third edge of the exposed first substrate after step d) Method of manufacturing a liquid crystal panel further comprising.

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